Review
Chemistry, Multidisciplinary
Stavros K. Kariofillis, Abigail G. Doyle
Summary: In recent years, the development of light-driven reactions has made significant advancements in synthetic organic chemistry, particularly in combining photoredox and nickel catalysis for challenging cross-coupling reactions. The question of whether photo-induced activation of the nickel catalyst itself could lead to new approaches to cross-coupling has been explored. By utilizing a visible-light-driven mechanism for chlorine radical formation and conducting mechanistic investigations on organometallic Ni complexes relevant to cross-coupling, the study aims to facilitate new catalyst design and develop novel synthetic methods.
ACCOUNTS OF CHEMICAL RESEARCH
(2021)
Article
Chemistry, Physical
Zuxiao Zhang, Duong T. Ngo, David A. Nagib
Summary: A dual catalytic strategy involving an Ir photocatalyst and a Cu complex enables regioselective amination and cross-coupling of allyl alcohols with various nucleophiles. This approach allows for the formation of N-radicals via an energy transfer mechanism followed by interception of alkyl radicals for radical amino-functionalizations of olefins. Insights into the nature of Cu-based radical interception are provided through stereo, regio, and kinetic probes.
Review
Chemistry, Multidisciplinary
Agnieszka Mikus, Beata Lopuszynska
Summary: This review discusses nitration reactions of porphyrin derivatives and their importance in providing valuable intermediates for further transformations. The introduction of NO2 group increases the electrophilic character of porphyrins, leading to a broad spectrum of subsequent reactions. This approach allows synthesizing complex porphyrin-like compounds, with nitration substitutions possible at various positions in the porphyrin systems.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Article
Chemistry, Applied
Lilian Geniller, Marc Taillefer, Florian Jaroschik, Alexis Prieto
Summary: The Ni-photoredox catalyzed desulfurative cross-coupling reaction enables the synthesis of various unsymmetrical diarylmethane molecules under mild reaction conditions, providing new transformations of abundant, naturally occurring thiols.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Physical
Dominik Birnthaler, Rok Narobe, Eliseo Lopez-Berguno, Christoph Haag, Burkhard Koenig
Summary: Ligand-to-metal charge transfer (LMCT) photo-catalysis enables the activation and utilization of halides and other heteroatoms in metal complexes. The application of bismuth LMCT in organic radical coupling reactions has been expanded, generating chlorine and carboxyl radicals in net-oxidative and redox-neutral photochemical reactions. The study reveals BiCl4- and BiCl52- as the catalytically active bismuth species under 385 nm irradiation, providing insight into the reactivity of the highly reactive bismuth(II) catalyst fragment through cyclic voltammetry and UV-vis studies.
Article
Chemistry, Multidisciplinary
Yujun Li, Jie Yang, Xinxin Geng, Pan Tao, Yanling Shen, Zhishan Su, Ke Zheng
Summary: This article presents a single-step radical approach for the modular synthesis of functionally diverse alpha-tertiary amino acids (ATAAs). The synthesis takes place under mild conditions without the use of metals, photocatalysts, or other additives. The method demonstrates broad functional group tolerance and late-stage applicability, as well as gram-scale synthesis via flow chemistry. Mechanistic studies reveal the key intermediate in the reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Ya-Ming Tian, Evamaria Hofmann, Wagner Silva, Xiang Pu, Didier Touraud, Ruth M. M. Gschwind, Werner Kunz, Burkhard Koenig
Summary: The amino alcohol meglumine solubilizes organic compounds in water and enforces the formation of electron donor acceptor (EDA) complexes, resulting in unique cross-coupling reactions. UV-A photoinduced electron transfer within the EDA complexes leads to the cleavage of halide ions and recombination of arenes, followed by rearomatization and proton loss. UV and NMR measurements demonstrate the significance of the EDA aggregates for the photoinduced reaction. Enforced EDA aggregate formation in water provides new activation modes for organic photochemical synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Zhilong Li, Leitao Huan, Jian Li, Xiaomin Shu, De Zhong, Wenjing Zhang, Haohua Huo
Summary: In this study, an unprecedented enantioselective cross-electrophile coupling (XEC) of α-amino acid derivatives with aryl bromides was achieved using alcohols as reducing agents via Ni/photoredox catalysis. The method utilizes photocatalytically generated α-hydroxyalkyl radicals to convert alkyl electrophiles to alkyl radicals that can selectively couple with aryl bromides. The scalable protocol allows modular access to valuable enantioenriched benzylic amines and can be applied to late-stage diversification with broad functional group tolerance. Mechanistic studies support the versatility of this alcohol-based reactivity for radical generation and subsequent asymmetric cross-coupling. We expect that this alcohol-based cross-coupling will serve as a general platform for the development of appealing yet challenging enantioselective XECs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Xiaoyu Tong, Ze-Peng Yang, Carlos E. Del Angel E. Aguilar, Gregory C. Fu
Summary: This study reports an iron catalyst for cross-coupling reactions of alkyl electrophiles using olefins and hydrosilanes instead of alkylmetal reagents. Carbon-carbon bond formation occurs at room temperature, and the method utilizes commercially available components. Mechanistic studies suggest the generation of an alkyl radical from the alkyl electrophile and reversible elementary steps.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Lewis Caiger, Huaibo Zhao, Timothee Constantin, James J. Douglas, Daniele Leonori
Summary: Here, a toolbox strategy for cross-coupling unactivated secondary alkyl iodides with various N-, O-, and C-based nucleophiles is described. This strategy utilizes photoredox-generated phenyl radicals to mediate halogen-atom transfer (XAT) and convert alkyl iodides into corresponding radicals. These radicals then undergo a second catalytic cycle mediated by copper, enabling C-N/O/C bond formation with the nucleophiles.
Article
Chemistry, Multidisciplinary
Xiaoye Yu, Constantin G. Daniliuc, Fatmah Ali Alasmary, Armido Studer
Summary: A new approach for the synthesis of alpha-aminosilanes using photoredox catalysis was presented, providing highly functionalized products in good yields under mild conditions. Both primary and secondary amines can be used for this transformation, and optically pure alpha-aminosilanes can be obtained by using chiral amines. Mechanistic studies indicate that the reactions proceed through radical/radical cross-coupling of silyl radicals with alpha-amino alkyl radicals.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Sandip Bag, Shubham Ojha, Sreelakshmi Venugopalan, Basudev Sahoo
Summary: In this study, we present a visible-light photoredox-catalyzed alkylation/arylative cyclization reaction of N-acrylamides with ketone-derived dihydroquinazolinones. This method allows the formation of indolo- and benzimidazolo[2,1-a]isoquinolines or 2-oxindoles from 2-arylindoles, 2-arylbenzimidazoles, or N-substituted anilines. The reaction proceeds through the formal cleavage of ketone α-C-C and arene C-H bonds, leading to the incorporation of alkyl and aryl carbogenic motifs and the synthesis of cyclic structures with a quaternary stereocenter.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Lijun Lu, Hao Li, Aiwen Lei
Summary: Oxidative cross-coupling reactions between two nucleophiles have become a significant tool in organic synthesis for constructing chemical bonds. This reaction model was discovered through the cross-coupling of two organometallic reagents and related mechanisms were revealed through the characterization of intermediates and study of reaction kinetics using operando spectroscopy. The reaction exhibits high atom and step economy, making it an ideal and economical process for synthesizing valuable chemicals.
CHINESE JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Richard R. Surgenor, Xiangqian Liu, Morgan J. H. Keenlyside, William Myers, Martin D. Smith
Summary: We report a new iron-catalyzed system that enables the direct coupling of naphthols and indoles to obtain atropisomeric heterobiaryl compounds with high enantioselectivity. The reaction exhibits remarkable chemoselectivity and exclusively produces cross-coupled products without competing homocoupling. Mechanistic investigations suggest the generation of an indole radical as an off-cycle event, with the reaction proceeding through the formation of a chiral Fe-bound naphthoxy radical that is trapped by a nucleophilic indole. This catalytic system is expected to provide access to a range of heterobiaryl compounds and facilitate their application in materials science, medicinal chemistry, and catalysis.
Article
Chemistry, Organic
Zuzana Buresova, Veronika Jandova, Milan Klikar, Monika Grygarova, Filip Bures
Summary: A photochemical cross-coupling protocol for synthesizing bi(hetero)aryls has been developed with the use of a dicyanopyrazine photoredox catalyst. The method allows for the coupling of various aromatic compounds with high yields.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Quan-Qing Zhao, Julia Rehbein, Oliver Reiser
Summary: This study presents a visible-light-driven dearomatization reaction of unactivated arenes, enabling efficient synthesis of spiro-1,4-cyclohexadienes. Calculations indicate that the overall process is thermoneutral, highlighting the potential of light-driven processes in developing sustainable transformations that defy thermodynamic requirements.
Review
Biochemistry & Molecular Biology
Bin Lu, Wen-Jing Xiao, Jia-Rong Chen
Summary: Visible-light photoredox catalysis has gained significant attention in the synthetic community due to its potential for sustainable and efficient activation of organic molecules. Amide synthesis through photoredox catalysis has become increasingly popular as it allows for the preparation of a wide variety of amides from halides, arenes, and alkanes using visible light irradiation. These methods offer an alternative to traditional amide synthesis strategies involving stoichiometric activating agents.
Article
Chemistry, Physical
Peng-Zi Wang, Yu-Jie Liang, Xue Wu, Wei Guan, Wen-Jing Xiao, Jia-Rong Chen
Summary: Atom transfer radical addition (ATRA) reaction of alkenes has a significant impact in the field of radical difunctionalization of alkenes. A novel copper-catalyzed asymmetric three-component photo-ATRA-type reaction is reported, which enables highly enantioselective intermolecular C-O cross-coupling between carbon radicals and carboxylic acids.
Review
Chemistry, Multidisciplinary
Peng-Zi Wang, Wen-Jing Xiao, Jia-Rong Chen
Summary: Creating, conserving, and modifying the stereochemistry of organic compounds is an important area of research in synthetic chemistry. Stereochemical editing, as an alternative strategy, allows for late-stage alteration of stereochemistry, but it often faces thermodynamic barriers. Photocatalysis, by using photogenerated radical species, can overcome these barriers and enable contra-thermodynamic stereochemical editing processes.
NATURE REVIEWS CHEMISTRY
(2023)
Editorial Material
Chemistry, Multidisciplinary
Peng-Zi Wang, Wen-Jing Xiao, Jia-Rong Chen
Summary: A general electrochemical strategy has been developed for the direct C-H carboxylation of N-heteroarenes with CO2, resulting in carboxylated products with excellent and tunable site selectivity. This study also opens up possibilities for regulating reactivity modes in electrochemical synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Jannik Reimler, Xiao-Ye Yu, Nico Spreckelmeyer, Constantin G. Daniliuc, Armido Studer
Summary: The Friedel-Crafts acylation reaction has been a valuable and versatile reaction, but a new radical approach for the acylation of arenes and heteroarenes is presented in this study. By using cooperative photoredox/NHC radical catalysis, C-H acylation is achieved with regiodivergent outcomes. Aroyl fluorides act as the acylation reagents in both the ionic and radical processes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Xue-Song Zhou, Zhihan Zhang, Wen-Yuan Qu, Xiao-Peng Liu, Wen-Jing Xiao, Min Jiang, Jia-Rong Chen
Summary: We report a cooperative catalytic system comprising a chiral nickel Lewis acid catalyst and an organic photocatalyst fueled by visible-light irradiation that allows for the hitherto elusive asymmetric [3 + 2] photocycloaddition of β-keto esters with vinyl azides under redox-neutral conditions. This protocol enables highly enantioselective construction of polycyclic densely substituted 3,4-dihydro-2H-pyrrole heterocycles featuring two contiguous tetrasubstituted carbon stereocenters, including a useful chiral N,O-ketal motif that is not easily accessible with other catalytic methods. Mechanistic studies revealed that the overall reactivity relies on the seamless integration of dual roles of nickel catalysts by the catalytic formation of the substrate/Ni complex, assisting both photoredox event and enantioselective radical addition.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
News Item
Chemistry, Multidisciplinary
Peng-Zi Wang, Jia-Rong Chen
Summary: In this study, N-N pyridinium ylides were used to generate triplet state diradicals through photoinduced energy transfer, and subsequent [3+2] cycloaddition with a tethered alkene allowed the synthesis of diverse ortho-pyridyl lactams.
Article
Chemistry, Multidisciplinary
Xue-Song Zhou, Zhihan Zhang, Wen-Yuan Qu, Xiao-Peng Liu, Wen-Jing Xiao, Min Jiang, Jia-Rong Chen
Summary: We report a cooperative catalytic system that enables the elusive asymmetric [3 + 2] photocycloaddition of beta-keto esters with vinyl azides under redox-neutral conditions, using a chiral nickel Lewis acid catalyst and an organic photocatalyst fueled by visible-light irradiation. This protocol allows for the highly enantioselective construction of polycyclic densely substituted 3,4-dihydro-2H-pyrrole heterocycles featuring two contiguous tetrasubstituted carbon stereocenters.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Guo-Qing Li, Fan-Rong Meng, Wen-Jing Xiao, Jia-Rong Chen
Summary: Catalytic radical difunctionalization of 1,3-enynes is a promising method for constructing valuable allenes and propargylic compounds. However, there has been limited progress in enantioselective radical 1,2-difunctionalization. In this study, a regio- and enantioselective radical three-component coupling of 1,3-enynes, oxime esters, and carboxylic acids through photoinduced copper catalysis is reported. This protocol demonstrates excellent enantioselectivity and provides access to a library of cyanoalkylated propargylic esters.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Guoqing Li, Jiarong Chen
Summary: In this study, a highly efficient, selective and atom-economical method for the construction of allylic amines is reported. The combination of a photoredox catalyst and cobaloxime catalyst enables site-selective allylic amination of various olefins with secondary alkyl amines, resulting in valuable tertiary aliphatic allylamines without the need for external oxidants.
GREEN SYNTHESIS AND CATALYSIS
(2022)
Review
Chemistry, Multidisciplinary
Dong Liang, Wenjing Xiao, Sami Lakhdar, Jiarong Chen
Summary: The study of the chemistry of axially chiral compounds has become increasingly important due to their widespread presence in various fields. Catalytic asymmetric radical reactions provide a complementary platform for the construction of enantiomerically enriched compounds, which are in high demand in the chemical and pharmaceutical industries. This review critically discusses recent achievements in this area based on different radical precursors and catalytic activation modes.
GREEN SYNTHESIS AND CATALYSIS
(2022)
Review
Chemistry, Organic
Gao Pan-Pan, Xiao Wen-Jing, Chen Jia-Rong
Summary: Alkenes and their derivatives are important building blocks in organic synthesis. Traditional synthetic methods have limitations, and photoredox catalysis has emerged as a powerful and promising platform for alkene synthesis due to its green chemistry characteristics and unique activation modes.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Shuang-Hua Xu, Dong-Mei Yan, Li Rao, Min Jiang, Ya-Li Wu, Wen-Jing Xiao, Jia-Rong Chen
Summary: This study reports a convenient strategy utilizing visible-light-driven proton-coupled electron transfer to decompose sulfur ylides into carbon radicals, enabling the construction of 1,2-hydroxyacylmethylation reactions. The method achieves high selectivity and demonstrates a wide range of applicability, shedding light on the mechanism and regioselectivity origin.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Review
Chemistry, Applied
Peng-Zi Wang, Wen-Jing Xiao, Jia-Rong Chen
Summary: This review critically illustrates the recent advances in radical-mediated transformations of 1,3-dienes based on different radical precursors and working modes. Special emphasis is given to the related mechanistic studies and synthetic applications.
CHINESE JOURNAL OF CATALYSIS
(2022)
